Electrical outlets



Jan. 19, 1965 R. H. PARKER 3,166,370

ELECTRICAL OUTLETS Filed April 13, 1962 S Sheets-Sheet l 5 &

I lllll INVENTOR. RICHARD H. PARKER BY 7%%4 %,@Mm

A TToR/VEY Jan. 19, 1965 R. H. PARKER 3,166,370

ELECTRICAL OUTLETS Filed April 13, 1962 3 Sheets-Sheet 2 mumnm 3 I I I INVENTOR. RICHARD H. PARKER FIG. 8 BY A TT'OR/VEY Jan. 19, 1965 R. H. PARKER Q 3,156,370

ELECTRICAL OUTLETS Filed April 15, 1962 3 Sheets-Sheet 3.

INVENTOR. RICHARD H. PARKER BY x A T ro /vsy United States Patent Ofifice 3,lfi6,370 Patented Jan. 19, 1965 3,166,370 ELECTRICAL OUTLETS Richard H. Parker, Lockbourne Air Force Base, Ohio (Rte. 3, Box 288, Seagoville, Tex.) Filed Apr. 13, 1962, Ser. No. 187,308 2 Claims. (Cl. 339-21) This invention relates to electrical outlets. More particularly, it relates to a completely safe continuous strip outlet and the attendent devices associated therewith.

Although numerous changes have been proposed and advocated for the conventional domestic outlet, very few of these have had any success. Much of this failure is attributable to the fact that many appliances and fixtures would require changes in the plugs to adapt them for use with a new type of outlet. Additionally, there is the considerable reluctance of many manufacturers to revise an apparently standardized product. This invention not only provides a new type of plug for use on appliances and fixtures as they are manufactured, but also provides adapters so that plugs that fit presently existing domestic outlets may be easily modified to fit the continuous strip safety outlet herein described.

Over the years, many serious accidents have occurred in and around the home because of the unsafe nature of the present common type of two prong socket. A good percentage of electrical injuries resulting from such accidents are caused by the insertion of conducting objects into the ungrounded or hot side of the receptacle while the person holding the conducting object is himself grounded. Such events are, unfortunately, most frequent with small children who have little or no knowledge of the dangers inherent in the innocent looking structure. According to this invention, a construction for an electrical outlet is provided that allows any conductive object to .be inserted into the outlet with no possibility of electrical shock to the individual who inserts the object.

The outlet strip construction according to this invention is versatile and attractive. The simplicity of its' construction allows it to conform to and fit into many molding designs that are used along the floors of homes. Further, since a single elongated slot for the outlet is used, and, since that slot may be very narrow, the outlet strip is adaptable for installation in many other areas in addition to the fioor molding becoming a part of the room design, well hidden, yet very serviceable.

The strip is readily extended in length by the bridging units provided as a part of this invention so that it can be manufactured in standard lengths. This invention also includes bridging units for connecting around and across the corners of rooms. The bridging units are simply inserted or plugged into the adjacent ends of two straight lengths bridging the gap between them.

Other advantages of the invention are apparent from the following specification, the drawings, and the claims.

In the drawings:

FIG. 1 is a partially cut away perspective view of the invention showing installation in the baseboard of a room.

FIG. 2 is a cross sectional view of the outlet strip.

FIG. 3 is a partially cut away perspective view showing the installation of a bridging adapter.

FIG. 4 is across sectional view of the outlet with a bridging adapter inserted into the outlet.

FIG. 5 is a sectional View of a plug for use in the outlet.

FIG. 6 is a perspective view of the disassembled plug of FIG. 5.

FIG. 7 is a perspective view of a bridging adapter for extending the length of the outlet strip.

FIG. 8 is a perspective view of'a bridging adapter for extending the outlet strip across the inside of a corner.

FIG. 9 is a perspective view of a bridging adapter for extending the outlet strip around the outside of a corner.

FIG. 10 is a perspective view, with portions cut away, of a circuit breaker for installation at the end of the outlet strip.

FIG. 11 is a sectional view of a construction for adapting a conventional plug for use with the outlet strip.

In the drawings, the same reference numerals are applied to identical parts in all figures and such identically numbered parts are substantially identical in structure, function, and operation. Therefore, to eliminate confusing duplication, these parts, their inter-relationship and their function will be described only in conjunction with a single embodiment, such description applying to all embodiments where these parts appear.

Referring to FIGS. 1 and 2, the outlet strip 11 comprises an elongated strip of insulating material 13 having a slot 15 running along its entire length. A strip 17 of resilient electrically conductive material is disposed at the back of the slot 15, and two strips 19 and 21 of resilient electrically conductive material are disposed near the opening of slot 15.

It is significant that strips 19 and 21 are arranged so that their inner edges 23 and 25, respectively, meet, making it impossible to insert any object into slot 15 without first contacting the strips 19 and 21. Strips 19 and 21 are connected by means of a suitable conductor 27 to ground, while the strip 17 is preferably connected to a circuit breaker 29 and then by a suitable conductor 31 to the ungrounded terminal of a source of electrical power. The circuit breaker unit 33 (FIG. 10) is preferably a separate unit easily attached to one end of the outlet strip 11.

As was stated, the two grounded strips 19 and 21 meet along their inner edges 23 and 25. The outer edges 35 and 37 of grounded strips 19 and 21, respectively, are embedded in the insulating material 13. The grounded strips 19 and 21 are resilient so that their edges 23 and 25 are forced apart when an object is inserted into slot 15 and come back together after it is removed. The positive strip 17 has an inner edge 39 projecting into the slot 15 and an outer edge 41 embedded in the insulating material 13. The hot strip 17 is also resilient, so that it yields to an object inserted into the slot.15. The inner edge 39 maintains good contact with the object because of its spring-like qualities, and returns to position after the object is removed from slot 15.

The construction described above prevents accidental electric shocks. Since no object can enter the slot 15 and contact the hot strip 17 without first contacting the grounded strips 19 and 21, the hot side of the outlet cannot be touched without first establishing a good ground through the object itself. Since a ground connection is established on the object first, when a conductive object is inserted into the slot 15, the object merely causes a short circuit when it is inserted far enough to contact the ungrounded strip 17. Therefore, no current can pass through the body of the individual holding the conductive object even though the individual may be grounded. The circuit breaker 29 interrupts the current to the outlet as a result of the short circuit or the usual domestic circuit breakers may function if no circuit breaker unit 33 is used at the inlet end of the outlet strip 11.

Although a variety of means may be used to mount the outlet strip 11 against the wall 43, the preferred construction is shown in FIGS. 1 and 2. One end 45 of a clamp 47 is embedded into each side 49 of the insulating material 13. The opposite end 51 of the clamp 47 is appropriately 'bent to fit along the wall support 53 and is attached thereto by any suitable means such as screws A convenient method of manufacturing the outlet strip 11 is in predetermined standard lengths, thus allowingfor interchangeability of like parts and mass production methods. Such a procedure would be disadvantageous however if the electrician had to then especially wire the lengths together. For this reason the bridging adapters 57, 59,.and 61 of FIGS. 7, 8, and 9, respectively, are provided. Standard lengths may be bridged together with the adapter 57 and special lengths of the outlet strip 11 may be obtained by simply cutting standard lengths to size with a hacksaw.

FIG. 7 shows the bridging adapter 57, which includes a strip of insulating material formed with a flat plate portion 63 and an enlarged semi-rounded edge 65. The two strips 67-67 of conductive material are positioned on opposite surfaces of plate portion 63 toward the edge opposite the semi-rounded edge 65. Two additional c onductive strips 69-69 are positioned on opposite surfaces of the plate portion 63 between strips 67-67 and the semi-rounded edge '65.

When the adapter 57 is inserted into the slot 15,. as shown in FIGS. 3 and 4 the adapter 57 bridges the gap 71 between two outlet strips 11-11. One of the strips 67-67 provides an electrical connection between the ungrounded strips 17-17 at the adjacent ends of two outlet strips 11-11. Similarly the strips 69-69 provide electrical connection between the grounded strips 19-19 and 21-21 at the adjacent ends of two outlet strips 11-11. The strips 57-67 and 69-69 are positioned on the fiat plate 63 to make these connections by bearing against strips 17, 19, and 21 when the adapter 57' is inserted fully into the slot 15.

FIGS. 8 and 9 illustrate adapter constructions for continuing the outlet strip 11 around corners. The adapter 59 of FIG. 8 is shaped to conform to an inside corner while the adapter 61 of FIG. 9 is shaped to conform to an outside corner. The essential difference between adapters 57, 59, and 61 is their shape with the various parts conforming to the shape required to serve the purpose of bridging the corner properly. The adapter 59 is shown installed in a corner of the room in FIG 3.

In addition to the regular circuit breakers provided in the circuits of the house, the outlet strip 11 may be pro vided with its own circuit breaker 33 as shown in FIGS. 1 and 10. The circuit breaker'33 plugs intothe outlet strip 11 in much the same manner as the adapters 57, 59, and 61. A fiat plate 71 of insulating material projects from the body 73 of the circuit breaker 33. The fiat plate 71 fits into the slot 15 of the outlet strip 11 and supports conductive strips 75-75 and 77-77. The conductive strips 75-75 contact the ungrounded strips 17 and the conductive strips 77-77 contact the grounded strips 23 and 25. The conductive strips 75-75 are connected through a circuit breaker 29 such as a push-button-reset type breaker as shown in FIGS. 1 and 10, by a conductor such as the lead 31 to the ungrounded side of the house circuit. The conductive strips 77-77 are connected by a conductor such as the lead 27 to the grounded side of the house circuit.

The above described circuit breaker unit 33 is convenient to use and is located in a readily accessable position. Each room outlet strip 11 that is used can be provided with the circuit breaker, if desired. The home owner then has an obvious and nearby check spot after a short circuit. A

Although the male plug for the outlet strip 11 may have a variety of possible shapes, the preferred form is shown in FIGS. and 6. The plug 79 has a cylindrical holder 81 of insulating material with a knob 33 at one end for convenience in handling. The contact support 85 also made of insulating material has a projection 87. A first conducting strip 89 passes through the center of the projection 87 and extends beyond the end 91 of projection 87, and a second conducting strip 93 covers one side of the projection 87 terminating short of the end 9 1. The

conductive strips 89 and $1 pass into the interior of the assembled plug 71 beneath wire holders such as screws disassemble, the contact holder '85 is rotated relative to the cylindrical holder 81 until the spring clips 101 register with the openings 103-103in the annular groove 4-9. By inserting a small screw driver or'other appropriate object into the openings 103-103 the spring clips 101-101 may be pushed out of engagement with the annular groove 99, so that the contact holder and cylindrical holder 81 can be pulled apart.

Obiously it would be somewhat inconvenient to replace the plugs on all of the fixtures and appliances in the home with the plug shown in FIGS; 5 and .6 by taking them apart and rewiring them. To eliminate such inconvenience a plug adapter 105 as shown in FIG. 11 may be provided. The contact holder 85 is practically identical to that shown in FIGS. 5 and 6 except for the prong receivers 107-107 which are connected to the ends of the conductive strips 89 and 93. The knob 83 is eliminated from the cylindrical holder 81' and is replaced by a flat end 109 having prong openings 111-11. The conventional plug 113, shown in FIG. 11 is provided with two prongs 115-115. Each prong 115 is invaribly provided with a hole 117. The prong receiver 107 has a.

small spring-like projection 119 slanted so as to retract and allow the end of the prong 115 to pass. The projections 119-119 then spring back upon registering with the holes 117-117 and lock the plug 113 to the plug 1115.

The two plugs 113 and 105 thus become an integral unit by simply pressing them together.

While the forms of the invention herein disclosed constitute preferred embodiments, it is not intended to describe or mention all of the possible equivalent forms or ramifications of the invention. It will be understood that the words used are terms of description rather than of limitation, and that various changes may be made Without departing from the spirit or scope of the invention.

Tosummarize, the present inventlon comprises an electric outlet including:

(a) An insulative member having an opening therein;

(b) At least one first conductive member in the opening;

(0) At least one second conductive member in the opening located farther than the at least one first conductive member (b) from the outer end of the opening;

(0.) The at least one first conductive member (b) being connected to a grounded line from an electrical voltage source, and the at least one second conductive member (c) being connected to at least one other lin from the electrical voltage source.

It is preferred that the at least one first conductive member (b) form a barrier between the outer end of the opening and the at least one scond conductive member (c), such that any conductive foreignobject inserted into the opening would be grounded before it could contact the at least one second conductive member (0).

In a preferred form of the invention, the electric outlet comprises: a

nected to a grounded line from an electrical voltage source, and the at least one second conductive strip being connected to at least one other line from the electrical voltage source.

Item (b) of the outlet preferably comprises a pair of resilient first conductive strips each attached to a side wall of the slot, near the opening thereof, and disposed along the length of the slot, the first conductive strips having contiguous edges substantially midway between the side walls of the slot. Item (0) of the outlet preferably comprises at least one resilient second conductive strip mounted in the slot farther than the first conductive strips (b) from the opening of the slot. It is desirable that the at least one conductive strip (0) be connected through a circuit breaker to the at least one ungrounded line from the electrical voltage source.

An electric outlet according to this invention may also be made up of a plurality of predetermined lengths of insulating material, each having a slot disposed lengthwise along one side thereof, with conductive strips (b) and (c) therein constructed, arranged, and connected as described above, and at least one means for connecting the conductive strips (b) and (0) respectively of adjacently disposed said predetermined lengths of insulating material (a) in straight lines and across and around corners; each said connecting means preferably including a flat plate sized to be insertable in adjacent said slots, and conductive strips on at least one surface of the flat plate positioned to bridge each conductive strip (b) and (0) respectively of said adjacent slots.

Useful in combination with an electric outlet according to this invention is a mating plug including a contact support of insulating material having a projection sized to fit said slot, a first contact strip passing through the center and extending beyond the end of the projection, a second contact strip disposed along one surface and terminating short of the end of the projection, each said contact strip being connected to a terminal on said contact support. One form of the mating plug serves also as an adapter to the present common type of plug. In this adapter plug, the terminals on the contact support are attached to conductive receivers positioned forinsertion of the prongs of a common tWo-pronged plug in contact therewith.

What is claimed is:

1. An electric outlet comprising:

(a) an elongated strip of insulating material having a slot disposed lengthwise along one side thereof;

(b) a pair of resilient first conductive strips each attached to a side Wall of said slot, near the opening thereof, and disposed along the length of said slot, said first conductive strips having contiguous edges substantially midway between the side walls of said slot and completely closing said slot;

(0) at least one resilient second conductive strip mounted in said slot farther than said first conductive strips (b) from the opening of said slot, and

disposed along the length of said slot;

(d) said pair of first conductive strips (b) being connected to a grounded line from an electrical voltage source, and said at least one second conductive strip (c) being connected to at least one other line from said other line from said electrical voltage source.

2. An electric outlet and mating plug comprising in combination:

(a) an elongated strip of insulating material having a slot disposed lengthwise along one side thereof;

(b) a pair of resilient first conductive strips each at tached to a side wall of said slot, near the opening thereof, and disposed along the length of said slot, said first conductive strips having contiguous edges substantially midway between the side walls of said slot and completely closing said slot;

(c) at least one resilient second conductive strip mounted in said slot farther than said first conductive strips (b) from the opening of said slot, and disposed along the length of said slot;

(d) said pair of first conductive strips (b) being connected to a grounded line from an electrical voltage source, and said at least one second conductive strip (c) being connected to at least one other line from said electrical voltage source;

(2) a plug including a contact support of insulating material having a projection inserted in said slot, at first contact strip passing through the center and extending beyond the end of said projection and in contact with said second conductive strip (c), a second contact strip disposed along one surface and terminating short of the end of said projection and in contact with one of said first conductive strips (b), said contact strips being connected respectively to conductive receivers positioned for insertion of the prongs of a common two-pronged plug in contact therewith and having means thereon for locking said prongs thereto.

References Cited by the Examiner UNITED STATES PATENTS 1,879,198 9/32 Greis 339-23 1,912,424 6/33 Batter 339-21 1,943,154 1/34 Zucker 339-21 1,955,531 4/34 Christopher 339-21 2,175,145 10/39 Davison 339-23 2,192,899 3/40 Edmonson 339-21 2,239,654 4/41 OBrien.

2,239,655 4/41 OBrien 339-23 X 2,283,398 5/42 Van Deventer 339-21 2,399,408 4/46 Walk 339-21 2,911,614 11/59 Davis 339-182 JOSEPH D. SEERS, Primary Examiner,

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,166,370 January 19, 1965 Richard H. Parker It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Column 4, line 30, for "111-11" read 111-111 line 62, for "scond" read second column 6,, line 7, strike out "said other line from".

Signed and sealed this 6th day of July 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. AN ELECTRIC OUTLET COMPRISING: (A) AN ELONGATED STRIP OF INSULATING MATERIAL HAVING A SLOT DISPOSED LENGTHWISE ALONG ONE SIDE THEREOF; (B) A PAIR OF RESILIENT FIRST CONDUCTIVE STRIPS EACH ATTACHED TO A SIDE WALL OF SAID SLOT, NEAR THE OPENING THEREOF, AND DISPOSED ALONG THE LENGTH OF SAID SLOT, SAID FIRST CONDUCTIVE STRIPS HAVING CONTIGUOUS EDGES SUBSTANTIALLY MIDWAY BETWEEN THE SIDE WALLS OF SAID SLOT AND COMPLETELY CLOSING SAID SLOT; (C) AT LEAST ONE RESILIENT SECOND CONDUCTIVE STRIP MOUNTED IN SAID SLOT FARTHER THAN SAID FIRST CONDUCTIVE STRIPS (B) FROM THE OPENING OF SAID SLOT, AND DISPOSED ALONG THE LENGTH OF SAID SLOT; (D) SAID PAIR OF FIRST CONDUCTIVE STRIPS (B) BEING CONNECTED TO A GROUNDED LINE FROM AN ELECTRICAL VOLTAGE SOURCE, AND SAID AT LEAST ONE SECOND CONDUCTIVE STRIP (C) BEING CONNECTED TO AT LEAST ONE OTHER LINE FROM SAID OTHER LINE FROM SAID ELECTRICAL VOLTAGE SOURCE. 